Breech mechanism for firearms



July 19, 1949. c. A. PERRY ETAL BREECH MEcnAmsM Fon FIIREARMS 5 Sheets-Sheet 1 Filed March 19, 1947 July 19, 1949. c. A. PERRY ET AL BREECH MECHANISM FOR FIREARMS 3 sheets-Sheet 2 Filed March 19, 1947 July 19 1949- c. A. PERRY ETAL 2,476,905

REECH MECHANISM FR FIREARMS Filed March 19, 1947 3 Sheets-Sheet 3 ATTD R N EYJ Patented July ^19, 1949 `UNITED STATES BREECH MECHANISM FOR FIREARMS Claude Alfred Perry, Olton, Roger David Wackrow, Handsworth, Birmingham, and Arthur Sydney Urry, Shirley, England, assignors to The Birmingham Small Arms Company Limited, Small Heath, Birmingham, England, a

British company Application March 19, 1947, Serial No. 735,560 In Great Britain October 24, 1945 Section 1, Public Law 690, August 8, 1946 Patent expires October 24, 1965 (Cl. l2-35) 7 Claims.

The present invention is concerned with improvements in or relating to firearms and is particularly, though by no means exclusively, concerned with small-bore firearms of the kind used for miniature target shooting at, for example, fun fairs.

Small-bore rearms as used at fun fairs are generally of the blow back type and an attendant inserts a plurality of cartridges in a tubular magazine in the butt end of the firearm. Such firearms must be robust and capable of standing up to mis-handling and ill-usage and particularly the action part of the rearm must be capable of being used more or less constantly over a period of hours.

It is an object of the invention to provide a novel and improved small-bore firearm which is robust and capable of being used continuously and satisfactorily over a period of hours.

According to the present invention, the breech mechanism of a firearm comprises a pivoted sector-shaped bifurcated breech block, a channel in said breech block formed by the limbs thereof and an arcuate web, and a sear member for holding the breech block in a retracted position against the action of a spring.

The breech block is pivotally mounted for oscillatory movement on a bottom plate, and has a groove formed in the periphery thereof to receive a projection on a sear also pivotally mounted on the bottom plate. A trip pawl is mounted on a trigger for contact with the sear to release the breech block to the action of a torsion spring so that a firing pin carried by the breech block will strike a cartridge in the firing chamber of the firearm. Cartridges are supplied to the firing chamber from a tubular magazine and pass through a feed tube the outlet end of which is situated adjacent the mouth of the iiring chamber. The feed tube is a pivotally mounted member and as the breech block is oscillated forwardly by its spring it is arranged to Contact the underside cf the tube and cam its forward end upwardly out of the way of the firing pin to allow the latter to strike the rimof a cartridge in the firing chamber.

In order that the nature of the present invention may become more clear a firearm illustrative thereof will now be more fully described with reference to the accompanying drawings, though it is to be understood that this has been selected for description merely by way of exemplication of the invention and not by way of limitation thereof,

In the said drawings:

Figure 1 is a left hand side elevation of the mid-portion of the illustrative firearm;

Figure 2 is a right hand cross-sectional view of the parts shown in Figure l;

Figure 3 is a view illustrating the position of various parts during cooking of the rearm;

Figure 4 is a view similar to Figure 3 but showing the parts in an uncooked position;

Figure 5 is a rear end elevation of a. breech block of the illustrative rearm;

Figure 6 is a section taken along the line VI-VI of Figure 5; I

Figure 7 is a front end view of the breech block showing particularly a. ring pin carried thereby.

Figure 8 is a view similar to Figure 2 but showing the parts in the positions' which they occupy at the instant of firing;

Figure 9 is a vertical transverse section on the line 9-9 in Figure 8 but showing the parts in cocked positiomand Figure 10 is a view similar to Figure 9 but showing the positions of the parts at the instant of firing.

The illustrative firearm comprises a bottom plate I adapted to be secured to the body 3 of the rearm, the plate being generally U-shaped in cross-section. Pivoted at 5 to the forward end of the bottom plate I is the front end of a combined cooking handle and trigger guard 1. Pivotally mounted upon the pivot pin 5 is a breech block 9 which comprises a sector-shaped member. The member is bifurcated, as is shown in Figure 5, and the two limbs are united by an arcuate cross web II which extends from the rear face of the member for a slight distance forwardly of the same, the space between the limbs and the inner wall of the web being adapted to form a channel for the passage of cartridge cases ejected from the breech chamber of the rearm. At the lower rear corners of the limbs of the breech block 9 are formed ears I3 (Figure 6) through which the pivot pin 5 passes and a torsion spring I5 coiled round the pivot pin tends normally to urge the breech block in a forward direction about the pivot 5. The periphery of the breech block 9 is provided with a notch I1 on its` rear face to co-operate with a projection or tooth I9 formed on the front face of a sear member 2| hereinafter to be described. Pivoted to the breech block 9 and extending along the underface of the web II is a cartridge extractor 23 which comprises a hooked forward end 25 (Figure 6). A torsion spring 21 surrounds the pivot of the extractor 23 and normally urges the hookshaped end upwardly. Adjacent the forward end face of the web one ci? .the limbs is vdrilled to provide accommodation for a laterally extending fir ing pin 29 (Figure 7) that stands proud of the web and is situated above the hook-shaped end of the extractor 23. The arrangement of the extractor 23 and pin 29 is such'that as the breech block 9 is rocked forwardlyitstorsion spring I the pin 29 will strike the base or a cartridge in the firing chamber of thefiiiearrn and the end of the extractor will engage the rim of the same.

The scar member ZI comprises a plate mounted on a pivot pin 3| passing through. oppositely posed webs on the bottom plate I.` In addition to,

the tooth I9 the member 2l has acam nger 33 which, during the forward closing movement .of the breech block, is arranged to be' acted upon by the peripheral face of the breech block Si, seen in Figure 4. At its upper rear corner the sear member is provided with a shoulder 35 for interengagement with a safety lever:y 3T (see Fig ures 1 and 2). The SQlF-member has a iaterally extending pin 39 secured thereon for engagement with one end of a torsion spring 4l which theren by serves to bias the member about its pivot 3l and urge the tooth AI!! inte the groove Il in the limb of the breech block.

Also pivoted on the plate I is a trigger i3 which at its .opper epd carries a pivoted trip pawl d5. The forward end f the. trip pawl d is Should-ered t0 engage @depending tail para@ of the Sear member 2| (see Figures 2v, 3 and 4) and 9J @Oil Spgr 41 SQCUQ* @li-9 9nd, t@ th@ rear of the eawl and. et its ether @ed te the bottom plate tends n lly to maintain vthe -Dawl in enea-sementwt the teil solstice Of. the sear member.

rEhe safety lever 31 is a forwardly extending member pivotally mounted at its rear. end to the action body and spring-urged downwardly into contact with a cross piny A9 carried by a downwardly extendingr lug 5I on a thumb slide 53. The safety lever 31 has a sloping under-surface which is provided with two small forwardly and rearwardly spaced recessess therein adapted to be engaged by the 9.135% Dili- 4'21 W'en @he thumb slide 53 is moved rearwardly the cross pin @il lies in the rearward recess; (jas seeninfl'igure 2) so that the lever 3'!Y is spr' rged downwardly to such a position that its forward end engages with the shoulder 35 on the scar member to prevent the latter. from movement. Sliding of theY thumb slide `fizgr-wardl y will cause the cross pin es to be engaged by theiorward recess which moves and holds the forward endoi the safety lever away from the shoulder on the sear niember.

Cartridges are locatedl in a tubular magazine 51 (Figure 2) formed in the butt of the rearm and are spring-urged forwardly into a clipper or feed tube 59 thevforward end of which is located adjacent the iiring chamber of the iirearm. The feedtube 5:9 is provided with a downwardly Projecting 111gthrough Ywhich passes e pivot pin El located in oppositely disposed webs in the bottom plate l. The feed tube 5,9- is acted upon by a secondY limb or the torsion spring lli in such manner as normally to maintain it in alignment with the iiring; chamber but the forward end of the tube islocated in the path of movement of the web Il of thefbreech block S.

Assuming the irearm to contain a charger of cartridges in its magazine and to be in uncooked postor;J the Spring in @he magazine Will urge the .As the breech block swings rearwardly a depression 6.5, formed in the periphery of the breech block il, adjacent to the notch Il, will contact the forwardly extending cam nger 33 of the sear member 2'I to allow the latter to be rocked slightly in a direction away from the safety lever to Vminimise danger of the sear member and the breech block becoming wedged together. As the breech blockY nears its cocked position the projection or tooth I 9 on the sear member will drop into the notch I'I to maintain the breech block in cocked position. Depression of the trigger will thereafter cause the pawl '45 thereon to rock .the scar member about its .pivot 3| to free. the Vbreech block to theA action of the spring I5 to allow the liring pin 23 to strike a cartridge and the extractor 23 to engage the case thereof. Upon discharge of the rearm, the breech block will be rocked rearwardly to cocked position once more. The pawl is so arranged that even if the trigger is maintained in its depressed posi@ tion the projection or. tooth on the sear member will engage the notch in the breech block to maintain theY latter cockedsine if the pawl were to occupy its forward position the lower rear corner of the breech block would then, in recoiling, deflect the pawl downwardly somewhat against the action of its spring,` to release the sear member and allow the tooth thereon to move into the notch in the breech block.

Having thus described our invention, what we claim as new and desire to secure by Letters Patent is:

1. A breech mechanism for 'a iirearm, comprising a pivoted sector-shaped bifurcated breech block having a channel formed between the limbs thereof and an arcuate web connecting the limbs, a ring pin and cartridge extractor carried by the' breech block, and a spring-actuated scar member for holding the. breech block in a retractedposition.

2. A breech mechanism. for a firearm, comprising a pivoted sectorfshaped bifurcated breech block having a notch in its periphery and a channel formed by the limbs thereof and having an arcuate web connecting the limbs, a ring pin and cartridge extractor disposed on said web and located rearwardly thereof relative to the breech chamber of the firearm, and a spring-actuated seal member cooperative with the breech block for holding the latter in a reu tracted position, said scar member comprising a plate having a projection engageable with the notch in the periphery of the breech block.

3. A breech mechanism `for a rearm, comprising a pivoted sector-shaped bifurcated breech lock having a channel formed by the limbs thereof and having an arcuate web connecting the,V limbs, a firing pin and cartridge extractor carried by the breech block, a spring-actuated sear member for holding the breech block in a retracted position, a movable trigger guard, and a projection on the trigger guard for retracting the breech block.

4.. A breech mechanism for a firearm, comprising a pivoted sector-shaped bifurcated breech block having a notch in its periphery and `a channel formed by the limbs thereof, and having an arcuate web connecting the limbs, a firing pin and cartridge extractor carried by the breech block, a spring-actuated sear member cooperative with the breech block for holding the latter in a retracted position comprising a plate having a projection engageable in the notch in the periphery of the breech block, and trigger actuated means contacting said sear plate to move the projection thereon out of engagement with the notch in the periphery of the breech block.

5. A breech mechanism for a rearm, comprising a pivoted sector-shaped bifurcated breech block having a notch in its periphery and a channel formed between the limbs thereof and having an arcuate web connecting the limbs, a ring pin and cartridge extractor carried by the breech block, a spring-actuated sear member for holding the breech block in a retracted position, comprising a plate having a projection thereon engaging in the notch in the periphery of the breech block, a trigger, means contacting with said sear plate to move the projection thereon out of engagement with said notch upon actuation of the trigger, and means comprising a safety lever movable into contact with said sear plate to prevent movement thereof upon actuation of the trigger.

6. A breech mechanism for a firearm having a. breech chamber, comprising a pivoted sectorshaped bifurcated breech block having a channel formed by the limbs thereof and having an arcuate web connecting the limbs, a iiring pin and cartridge extractor carried by the breech block, and a pivotally mounted tube lying between the limbs of the breech block to receive cartridges from a magazine and operative to feed the cartridges successively to the breech chamber.

7. A breech mechanism for a firearm having a breech chamber, comprising a pivoted sectorshaped bifurcated breech block having a channel formed between the limbs thereof and having an arcuate web connecting the limbs, a firing pin and cartridge extractor carried by the breech block, and a pivotally mounted cartridge feed tube lying between the limbs of the breech block, said tube being engageable by the arcuate web on retraction of the breech block and movable thereby away from the breech chamber.

CLAUDE ALFRED PERRY. ROGER DAVID WACKROW. ARTHUR SYDNEY URRY.

Country Date Great Britain 1889 Number 

